AB0095 EARLY INCREASED SYNOVIAL IMMUNOHISTOCHEMISTRY REACTIVITY OF IL17A AND TGF-Β1 IN PSORIATIC ARTHRITIS AND RHEUMATOID ARTHRITIS PATIENTS PREDICTING USE OF BIOLOGICS
Authors: K. Carpio, J. Pinto-Tasende, M. Fernandez-Moreno, M. E. Vazquez Mosquera, C. Fernández-López, N. Oreiro, F. J. De-Toro-Santos, F. J. Blanco
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> PsA diagnosis and treatment delayed is commonly leading to progressive articular damage, and research has aimed to improve PsA diagnosis and prognosis by identifying novel disease biomarkers. <h3>Objectives</h3> The present research aimed to analyze cytokines regarding inflammation and bone destruction/regeneration in patients with psoriatic arthritis (PsA), rheumatoid arthritis (RA), osteoarthritis (OA), and ankylosing spondylitis (AS) as possible biomarkers. <h3>Methods</h3> The patients underwent knee arthroscopy between 2009 and 2013 because they clinically presented with knee joint swelling and tenderness that did not improve with the medical treatment indicated for their diagnosed disease. So, samples were obtained from the swollen knee of patients who had been referred for undergoing arthroscopies and the synovial membrane was processed for pathological description, and protein IHC quantification (% Expressed in Ratio_Area-Intensity) for TGF-β1, IL-23, IL-6, IL-17A, IL-22, Dkk1, Sclerostin, BMP2, BMP4, Wnt1, and Wnt5a was done. All these data were analyzed and compared with the demographic, clinical, analytical, and radiological characteristics of the patients, and their predictive abilities using receiver operating characteristic (ROC) curves. <h3>Results</h3> Synovial membrane samples were obtained from 44 patients (PsA n=13, RA n=9, OA n=18, AS=4) for IHC quantification analysis. At baseline, 9 patients were being treated with csDMARDs, and no one of them was previosly treated with biologics. After 5 years, 4 of 13 with PsA and 2 of 9 the RA patients were treated with biologics. In general, early IHC reactivity for TGF-β1 in the synovial tissue was higher in patients with psoriatic arthritis (p=0.024) and was positively correlated with IL-17A (r = 0.355, p = 0.024), and Dkk1 (r = 0.444, p = 0.004). Early IHC reactivity for TGF-β1 in the synovial tissue was higher in PsA patients treated after with biologics (p = 0.015). Patients with PsA and RA treated with biologics had higher IHC reactivity for IL-17A in the synovial tissue (p = 0.004), for Dkk1 (p = 0.02), and for BMP2 (p = 0.045). There were no differences found regarding gender (p = 0.944), age (p = 0.947), or the Kellgren-Lawrence scale in the knee target (p = 0.608) for TGF-β1 but IL-17A IHC expression was higher in men (p = 0.02). In the logistic regression analysis, these differences seem to be independent of age, gender, or csDMARD use at the basal moment, for TGF-β1 (p=0.014), IL-17A (p=0.009), and Dkk1 (p=0.015). ROC curve analysis of IHC reactivity for TGF-β1 and IL-17A in the synovial seems to predict future treatment with biologics in the next 10 years with the areas under the curve (AUC) of 0.835 (95% CI: 0.695-0.976; p &lt; 0.006), and 0.853 (95% CI: 0.725-0.980; p &lt; 0.004), respectively. <h3>Conclusion</h3> It was observed that IHC reactivity for TGF-β1 and IL17A was higher in patients who needed biologics after 5 years of following. Early increased synovial immunohistochemistry reactivity of IL17A and TGF-β1 in psoriatic arthritis and rheumatoid arthritis patients could predict the need to use biologics. <h3>Funding sources</h3> Grant (PI11/00390) from Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica 2008-2011 and co-financed by the ISCIII-Subdirección General de Evaluación y Fomento de la Investigación - Fondo Europeo de Desarrollo Regional (FEDER). <h3>Disclosure of Interests</h3> None Declared.